1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Copyright (c) International Business Machines Corp., 2006 4 * Copyright (c) Nokia Corporation, 2007 5 * 6 * Author: Artem Bityutskiy (Битюцкий Артём), 7 * Frank Haverkamp 8 */ 9 10 /* 11 * This file includes UBI initialization and building of UBI devices. 12 * 13 * When UBI is initialized, it attaches all the MTD devices specified as the 14 * module load parameters or the kernel boot parameters. If MTD devices were 15 * specified, UBI does not attach any MTD device, but it is possible to do 16 * later using the "UBI control device". 17 */ 18 19 #include <linux/err.h> 20 #include <linux/module.h> 21 #include <linux/moduleparam.h> 22 #include <linux/stringify.h> 23 #include <linux/namei.h> 24 #include <linux/stat.h> 25 #include <linux/miscdevice.h> 26 #include <linux/mtd/partitions.h> 27 #include <linux/log2.h> 28 #include <linux/kthread.h> 29 #include <linux/kernel.h> 30 #include <linux/of.h> 31 #include <linux/slab.h> 32 #include <linux/major.h> 33 #include "ubi.h" 34 35 /* Maximum length of the 'mtd=' parameter */ 36 #define MTD_PARAM_LEN_MAX 64 37 38 /* Maximum number of comma-separated items in the 'mtd=' parameter */ 39 #define MTD_PARAM_MAX_COUNT 6 40 41 /* Maximum value for the number of bad PEBs per 1024 PEBs */ 42 #define MAX_MTD_UBI_BEB_LIMIT 768 43 44 #ifdef CONFIG_MTD_UBI_MODULE 45 #define ubi_is_module() 1 46 #else 47 #define ubi_is_module() 0 48 #endif 49 50 /** 51 * struct mtd_dev_param - MTD device parameter description data structure. 52 * @name: MTD character device node path, MTD device name, or MTD device number 53 * string 54 * @ubi_num: UBI number 55 * @vid_hdr_offs: VID header offset 56 * @max_beb_per1024: maximum expected number of bad PEBs per 1024 PEBs 57 * @enable_fm: enable fastmap when value is non-zero 58 * @need_resv_pool: reserve pool->max_size pebs when value is none-zero 59 */ 60 struct mtd_dev_param { 61 char name[MTD_PARAM_LEN_MAX]; 62 int ubi_num; 63 int vid_hdr_offs; 64 int max_beb_per1024; 65 int enable_fm; 66 int need_resv_pool; 67 }; 68 69 /* Numbers of elements set in the @mtd_dev_param array */ 70 static int mtd_devs; 71 72 /* MTD devices specification parameters */ 73 static struct mtd_dev_param mtd_dev_param[UBI_MAX_DEVICES]; 74 #ifdef CONFIG_MTD_UBI_FASTMAP 75 /* UBI module parameter to enable fastmap automatically on non-fastmap images */ 76 static bool fm_autoconvert; 77 static bool fm_debug; 78 #endif 79 80 /* Slab cache for wear-leveling entries */ 81 struct kmem_cache *ubi_wl_entry_slab; 82 83 /* UBI control character device */ 84 static struct miscdevice ubi_ctrl_cdev = { 85 .minor = MISC_DYNAMIC_MINOR, 86 .name = "ubi_ctrl", 87 .fops = &ubi_ctrl_cdev_operations, 88 }; 89 90 /* All UBI devices in system */ 91 static struct ubi_device *ubi_devices[UBI_MAX_DEVICES]; 92 93 /* Serializes UBI devices creations and removals */ 94 DEFINE_MUTEX(ubi_devices_mutex); 95 96 /* Protects @ubi_devices, @ubi->ref_count and @ubi->is_dead */ 97 static DEFINE_SPINLOCK(ubi_devices_lock); 98 99 /* "Show" method for files in '/<sysfs>/class/ubi/' */ 100 /* UBI version attribute ('/<sysfs>/class/ubi/version') */ 101 static ssize_t version_show(const struct class *class, const struct class_attribute *attr, 102 char *buf) 103 { 104 return sprintf(buf, "%d\n", UBI_VERSION); 105 } 106 static CLASS_ATTR_RO(version); 107 108 static struct attribute *ubi_class_attrs[] = { 109 &class_attr_version.attr, 110 NULL, 111 }; 112 ATTRIBUTE_GROUPS(ubi_class); 113 114 /* Root UBI "class" object (corresponds to '/<sysfs>/class/ubi/') */ 115 struct class ubi_class = { 116 .name = UBI_NAME_STR, 117 .class_groups = ubi_class_groups, 118 }; 119 120 static ssize_t dev_attribute_show(struct device *dev, 121 struct device_attribute *attr, char *buf); 122 123 /* UBI device attributes (correspond to files in '/<sysfs>/class/ubi/ubiX') */ 124 static struct device_attribute dev_eraseblock_size = 125 __ATTR(eraseblock_size, S_IRUGO, dev_attribute_show, NULL); 126 static struct device_attribute dev_avail_eraseblocks = 127 __ATTR(avail_eraseblocks, S_IRUGO, dev_attribute_show, NULL); 128 static struct device_attribute dev_total_eraseblocks = 129 __ATTR(total_eraseblocks, S_IRUGO, dev_attribute_show, NULL); 130 static struct device_attribute dev_volumes_count = 131 __ATTR(volumes_count, S_IRUGO, dev_attribute_show, NULL); 132 static struct device_attribute dev_max_ec = 133 __ATTR(max_ec, S_IRUGO, dev_attribute_show, NULL); 134 static struct device_attribute dev_reserved_for_bad = 135 __ATTR(reserved_for_bad, S_IRUGO, dev_attribute_show, NULL); 136 static struct device_attribute dev_bad_peb_count = 137 __ATTR(bad_peb_count, S_IRUGO, dev_attribute_show, NULL); 138 static struct device_attribute dev_max_vol_count = 139 __ATTR(max_vol_count, S_IRUGO, dev_attribute_show, NULL); 140 static struct device_attribute dev_min_io_size = 141 __ATTR(min_io_size, S_IRUGO, dev_attribute_show, NULL); 142 static struct device_attribute dev_bgt_enabled = 143 __ATTR(bgt_enabled, S_IRUGO, dev_attribute_show, NULL); 144 static struct device_attribute dev_mtd_num = 145 __ATTR(mtd_num, S_IRUGO, dev_attribute_show, NULL); 146 static struct device_attribute dev_ro_mode = 147 __ATTR(ro_mode, S_IRUGO, dev_attribute_show, NULL); 148 149 /** 150 * ubi_volume_notify - send a volume change notification. 151 * @ubi: UBI device description object 152 * @vol: volume description object of the changed volume 153 * @ntype: notification type to send (%UBI_VOLUME_ADDED, etc) 154 * 155 * This is a helper function which notifies all subscribers about a volume 156 * change event (creation, removal, re-sizing, re-naming, updating). Returns 157 * zero in case of success and a negative error code in case of failure. 158 */ 159 int ubi_volume_notify(struct ubi_device *ubi, struct ubi_volume *vol, int ntype) 160 { 161 int ret; 162 struct ubi_notification nt; 163 164 ubi_do_get_device_info(ubi, &nt.di); 165 ubi_do_get_volume_info(ubi, vol, &nt.vi); 166 167 switch (ntype) { 168 case UBI_VOLUME_ADDED: 169 case UBI_VOLUME_REMOVED: 170 case UBI_VOLUME_RESIZED: 171 case UBI_VOLUME_RENAMED: 172 ret = ubi_update_fastmap(ubi); 173 if (ret) 174 ubi_msg(ubi, "Unable to write a new fastmap: %i", ret); 175 } 176 177 return blocking_notifier_call_chain(&ubi_notifiers, ntype, &nt); 178 } 179 180 /** 181 * ubi_notify_all - send a notification to all volumes. 182 * @ubi: UBI device description object 183 * @ntype: notification type to send (%UBI_VOLUME_ADDED, etc) 184 * @nb: the notifier to call 185 * 186 * This function walks all volumes of UBI device @ubi and sends the @ntype 187 * notification for each volume. If @nb is %NULL, then all registered notifiers 188 * are called, otherwise only the @nb notifier is called. Returns the number of 189 * sent notifications. 190 */ 191 int ubi_notify_all(struct ubi_device *ubi, int ntype, struct notifier_block *nb) 192 { 193 struct ubi_notification nt; 194 int i, count = 0; 195 196 ubi_do_get_device_info(ubi, &nt.di); 197 198 mutex_lock(&ubi->device_mutex); 199 for (i = 0; i < ubi->vtbl_slots; i++) { 200 /* 201 * Since the @ubi->device is locked, and we are not going to 202 * change @ubi->volumes, we do not have to lock 203 * @ubi->volumes_lock. 204 */ 205 if (!ubi->volumes[i]) 206 continue; 207 208 ubi_do_get_volume_info(ubi, ubi->volumes[i], &nt.vi); 209 if (nb) 210 nb->notifier_call(nb, ntype, &nt); 211 else 212 blocking_notifier_call_chain(&ubi_notifiers, ntype, 213 &nt); 214 count += 1; 215 } 216 mutex_unlock(&ubi->device_mutex); 217 218 return count; 219 } 220 221 /** 222 * ubi_enumerate_volumes - send "add" notification for all existing volumes. 223 * @nb: the notifier to call 224 * 225 * This function walks all UBI devices and volumes and sends the 226 * %UBI_VOLUME_ADDED notification for each volume. If @nb is %NULL, then all 227 * registered notifiers are called, otherwise only the @nb notifier is called. 228 * Returns the number of sent notifications. 229 */ 230 int ubi_enumerate_volumes(struct notifier_block *nb) 231 { 232 int i, count = 0; 233 234 /* 235 * Since the @ubi_devices_mutex is locked, and we are not going to 236 * change @ubi_devices, we do not have to lock @ubi_devices_lock. 237 */ 238 for (i = 0; i < UBI_MAX_DEVICES; i++) { 239 struct ubi_device *ubi = ubi_devices[i]; 240 241 if (!ubi) 242 continue; 243 count += ubi_notify_all(ubi, UBI_VOLUME_ADDED, nb); 244 } 245 246 return count; 247 } 248 249 /** 250 * ubi_get_device - get UBI device. 251 * @ubi_num: UBI device number 252 * 253 * This function returns UBI device description object for UBI device number 254 * @ubi_num, or %NULL if the device does not exist. This function increases the 255 * device reference count to prevent removal of the device. In other words, the 256 * device cannot be removed if its reference count is not zero. 257 */ 258 struct ubi_device *ubi_get_device(int ubi_num) 259 { 260 struct ubi_device *ubi; 261 262 spin_lock(&ubi_devices_lock); 263 ubi = ubi_devices[ubi_num]; 264 if (ubi && ubi->is_dead) 265 ubi = NULL; 266 267 if (ubi) { 268 ubi_assert(ubi->ref_count >= 0); 269 ubi->ref_count += 1; 270 get_device(&ubi->dev); 271 } 272 spin_unlock(&ubi_devices_lock); 273 274 return ubi; 275 } 276 277 /** 278 * ubi_put_device - drop an UBI device reference. 279 * @ubi: UBI device description object 280 */ 281 void ubi_put_device(struct ubi_device *ubi) 282 { 283 spin_lock(&ubi_devices_lock); 284 ubi->ref_count -= 1; 285 put_device(&ubi->dev); 286 spin_unlock(&ubi_devices_lock); 287 } 288 289 /** 290 * ubi_get_by_major - get UBI device by character device major number. 291 * @major: major number 292 * 293 * This function is similar to 'ubi_get_device()', but it searches the device 294 * by its major number. 295 */ 296 struct ubi_device *ubi_get_by_major(int major) 297 { 298 int i; 299 struct ubi_device *ubi; 300 301 spin_lock(&ubi_devices_lock); 302 for (i = 0; i < UBI_MAX_DEVICES; i++) { 303 ubi = ubi_devices[i]; 304 if (ubi && !ubi->is_dead && MAJOR(ubi->cdev.dev) == major) { 305 ubi_assert(ubi->ref_count >= 0); 306 ubi->ref_count += 1; 307 get_device(&ubi->dev); 308 spin_unlock(&ubi_devices_lock); 309 return ubi; 310 } 311 } 312 spin_unlock(&ubi_devices_lock); 313 314 return NULL; 315 } 316 317 /** 318 * ubi_major2num - get UBI device number by character device major number. 319 * @major: major number 320 * 321 * This function searches UBI device number object by its major number. If UBI 322 * device was not found, this function returns -ENODEV, otherwise the UBI device 323 * number is returned. 324 */ 325 int ubi_major2num(int major) 326 { 327 int i, ubi_num = -ENODEV; 328 329 spin_lock(&ubi_devices_lock); 330 for (i = 0; i < UBI_MAX_DEVICES; i++) { 331 struct ubi_device *ubi = ubi_devices[i]; 332 333 if (ubi && !ubi->is_dead && MAJOR(ubi->cdev.dev) == major) { 334 ubi_num = ubi->ubi_num; 335 break; 336 } 337 } 338 spin_unlock(&ubi_devices_lock); 339 340 return ubi_num; 341 } 342 343 /* "Show" method for files in '/<sysfs>/class/ubi/ubiX/' */ 344 static ssize_t dev_attribute_show(struct device *dev, 345 struct device_attribute *attr, char *buf) 346 { 347 ssize_t ret; 348 struct ubi_device *ubi; 349 350 /* 351 * The below code looks weird, but it actually makes sense. We get the 352 * UBI device reference from the contained 'struct ubi_device'. But it 353 * is unclear if the device was removed or not yet. Indeed, if the 354 * device was removed before we increased its reference count, 355 * 'ubi_get_device()' will return -ENODEV and we fail. 356 * 357 * Remember, 'struct ubi_device' is freed in the release function, so 358 * we still can use 'ubi->ubi_num'. 359 */ 360 ubi = container_of(dev, struct ubi_device, dev); 361 362 if (attr == &dev_eraseblock_size) 363 ret = sprintf(buf, "%d\n", ubi->leb_size); 364 else if (attr == &dev_avail_eraseblocks) 365 ret = sprintf(buf, "%d\n", ubi->avail_pebs); 366 else if (attr == &dev_total_eraseblocks) 367 ret = sprintf(buf, "%d\n", ubi->good_peb_count); 368 else if (attr == &dev_volumes_count) 369 ret = sprintf(buf, "%d\n", ubi->vol_count - UBI_INT_VOL_COUNT); 370 else if (attr == &dev_max_ec) 371 ret = sprintf(buf, "%d\n", ubi->max_ec); 372 else if (attr == &dev_reserved_for_bad) 373 ret = sprintf(buf, "%d\n", ubi->beb_rsvd_pebs); 374 else if (attr == &dev_bad_peb_count) 375 ret = sprintf(buf, "%d\n", ubi->bad_peb_count); 376 else if (attr == &dev_max_vol_count) 377 ret = sprintf(buf, "%d\n", ubi->vtbl_slots); 378 else if (attr == &dev_min_io_size) 379 ret = sprintf(buf, "%d\n", ubi->min_io_size); 380 else if (attr == &dev_bgt_enabled) 381 ret = sprintf(buf, "%d\n", ubi->thread_enabled); 382 else if (attr == &dev_mtd_num) 383 ret = sprintf(buf, "%d\n", ubi->mtd->index); 384 else if (attr == &dev_ro_mode) 385 ret = sprintf(buf, "%d\n", ubi->ro_mode); 386 else 387 ret = -EINVAL; 388 389 return ret; 390 } 391 392 static struct attribute *ubi_dev_attrs[] = { 393 &dev_eraseblock_size.attr, 394 &dev_avail_eraseblocks.attr, 395 &dev_total_eraseblocks.attr, 396 &dev_volumes_count.attr, 397 &dev_max_ec.attr, 398 &dev_reserved_for_bad.attr, 399 &dev_bad_peb_count.attr, 400 &dev_max_vol_count.attr, 401 &dev_min_io_size.attr, 402 &dev_bgt_enabled.attr, 403 &dev_mtd_num.attr, 404 &dev_ro_mode.attr, 405 NULL 406 }; 407 ATTRIBUTE_GROUPS(ubi_dev); 408 409 static void dev_release(struct device *dev) 410 { 411 struct ubi_device *ubi = container_of(dev, struct ubi_device, dev); 412 413 kfree(ubi); 414 } 415 416 /** 417 * kill_volumes - destroy all user volumes. 418 * @ubi: UBI device description object 419 */ 420 static void kill_volumes(struct ubi_device *ubi) 421 { 422 int i; 423 424 for (i = 0; i < ubi->vtbl_slots; i++) 425 if (ubi->volumes[i]) 426 ubi_free_volume(ubi, ubi->volumes[i]); 427 } 428 429 /** 430 * uif_init - initialize user interfaces for an UBI device. 431 * @ubi: UBI device description object 432 * 433 * This function initializes various user interfaces for an UBI device. If the 434 * initialization fails at an early stage, this function frees all the 435 * resources it allocated, returns an error. 436 * 437 * This function returns zero in case of success and a negative error code in 438 * case of failure. 439 */ 440 static int uif_init(struct ubi_device *ubi) 441 { 442 int i, err; 443 dev_t dev; 444 445 sprintf(ubi->ubi_name, UBI_NAME_STR "%d", ubi->ubi_num); 446 447 /* 448 * Major numbers for the UBI character devices are allocated 449 * dynamically. Major numbers of volume character devices are 450 * equivalent to ones of the corresponding UBI character device. Minor 451 * numbers of UBI character devices are 0, while minor numbers of 452 * volume character devices start from 1. Thus, we allocate one major 453 * number and ubi->vtbl_slots + 1 minor numbers. 454 */ 455 err = alloc_chrdev_region(&dev, 0, ubi->vtbl_slots + 1, ubi->ubi_name); 456 if (err) { 457 ubi_err(ubi, "cannot register UBI character devices"); 458 return err; 459 } 460 461 ubi->dev.devt = dev; 462 463 ubi_assert(MINOR(dev) == 0); 464 cdev_init(&ubi->cdev, &ubi_cdev_operations); 465 dbg_gen("%s major is %u", ubi->ubi_name, MAJOR(dev)); 466 ubi->cdev.owner = THIS_MODULE; 467 468 dev_set_name(&ubi->dev, UBI_NAME_STR "%d", ubi->ubi_num); 469 err = cdev_device_add(&ubi->cdev, &ubi->dev); 470 if (err) 471 goto out_unreg; 472 473 for (i = 0; i < ubi->vtbl_slots; i++) 474 if (ubi->volumes[i]) { 475 err = ubi_add_volume(ubi, ubi->volumes[i]); 476 if (err) { 477 ubi_err(ubi, "cannot add volume %d", i); 478 ubi->volumes[i] = NULL; 479 goto out_volumes; 480 } 481 } 482 483 return 0; 484 485 out_volumes: 486 kill_volumes(ubi); 487 cdev_device_del(&ubi->cdev, &ubi->dev); 488 out_unreg: 489 unregister_chrdev_region(ubi->cdev.dev, ubi->vtbl_slots + 1); 490 ubi_err(ubi, "cannot initialize UBI %s, error %d", 491 ubi->ubi_name, err); 492 return err; 493 } 494 495 /** 496 * uif_close - close user interfaces for an UBI device. 497 * @ubi: UBI device description object 498 * 499 * Note, since this function un-registers UBI volume device objects (@vol->dev), 500 * the memory allocated voe the volumes is freed as well (in the release 501 * function). 502 */ 503 static void uif_close(struct ubi_device *ubi) 504 { 505 kill_volumes(ubi); 506 cdev_device_del(&ubi->cdev, &ubi->dev); 507 unregister_chrdev_region(ubi->cdev.dev, ubi->vtbl_slots + 1); 508 } 509 510 /** 511 * ubi_free_volumes_from - free volumes from specific index. 512 * @ubi: UBI device description object 513 * @from: the start index used for volume free. 514 */ 515 static void ubi_free_volumes_from(struct ubi_device *ubi, int from) 516 { 517 int i; 518 519 for (i = from; i < ubi->vtbl_slots + UBI_INT_VOL_COUNT; i++) { 520 if (!ubi->volumes[i] || ubi->volumes[i]->is_dead) 521 continue; 522 ubi_eba_replace_table(ubi->volumes[i], NULL); 523 ubi_fastmap_destroy_checkmap(ubi->volumes[i]); 524 kfree(ubi->volumes[i]); 525 ubi->volumes[i] = NULL; 526 } 527 } 528 529 /** 530 * ubi_free_all_volumes - free all volumes. 531 * @ubi: UBI device description object 532 */ 533 void ubi_free_all_volumes(struct ubi_device *ubi) 534 { 535 ubi_free_volumes_from(ubi, 0); 536 } 537 538 /** 539 * ubi_free_internal_volumes - free internal volumes. 540 * @ubi: UBI device description object 541 */ 542 void ubi_free_internal_volumes(struct ubi_device *ubi) 543 { 544 ubi_free_volumes_from(ubi, ubi->vtbl_slots); 545 } 546 547 static int get_bad_peb_limit(const struct ubi_device *ubi, int max_beb_per1024) 548 { 549 int limit, device_pebs; 550 uint64_t device_size; 551 552 if (!max_beb_per1024) { 553 /* 554 * Since max_beb_per1024 has not been set by the user in either 555 * the cmdline or Kconfig, use mtd_max_bad_blocks to set the 556 * limit if it is supported by the device. 557 */ 558 limit = mtd_max_bad_blocks(ubi->mtd, 0, ubi->mtd->size); 559 if (limit < 0) 560 return 0; 561 return limit; 562 } 563 564 /* 565 * Here we are using size of the entire flash chip and 566 * not just the MTD partition size because the maximum 567 * number of bad eraseblocks is a percentage of the 568 * whole device and bad eraseblocks are not fairly 569 * distributed over the flash chip. So the worst case 570 * is that all the bad eraseblocks of the chip are in 571 * the MTD partition we are attaching (ubi->mtd). 572 */ 573 device_size = mtd_get_device_size(ubi->mtd); 574 device_pebs = mtd_div_by_eb(device_size, ubi->mtd); 575 limit = mult_frac(device_pebs, max_beb_per1024, 1024); 576 577 /* Round it up */ 578 if (mult_frac(limit, 1024, max_beb_per1024) < device_pebs) 579 limit += 1; 580 581 return limit; 582 } 583 584 /** 585 * io_init - initialize I/O sub-system for a given UBI device. 586 * @ubi: UBI device description object 587 * @max_beb_per1024: maximum expected number of bad PEB per 1024 PEBs 588 * 589 * If @ubi->vid_hdr_offset or @ubi->leb_start is zero, default offsets are 590 * assumed: 591 * o EC header is always at offset zero - this cannot be changed; 592 * o VID header starts just after the EC header at the closest address 593 * aligned to @io->hdrs_min_io_size; 594 * o data starts just after the VID header at the closest address aligned to 595 * @io->min_io_size 596 * 597 * This function returns zero in case of success and a negative error code in 598 * case of failure. 599 */ 600 static int io_init(struct ubi_device *ubi, int max_beb_per1024) 601 { 602 dbg_gen("sizeof(struct ubi_ainf_peb) %zu", sizeof(struct ubi_ainf_peb)); 603 dbg_gen("sizeof(struct ubi_wl_entry) %zu", sizeof(struct ubi_wl_entry)); 604 605 if (ubi->mtd->numeraseregions != 0) { 606 /* 607 * Some flashes have several erase regions. Different regions 608 * may have different eraseblock size and other 609 * characteristics. It looks like mostly multi-region flashes 610 * have one "main" region and one or more small regions to 611 * store boot loader code or boot parameters or whatever. I 612 * guess we should just pick the largest region. But this is 613 * not implemented. 614 */ 615 ubi_err(ubi, "multiple regions, not implemented"); 616 return -EINVAL; 617 } 618 619 if (ubi->vid_hdr_offset < 0) 620 return -EINVAL; 621 622 /* 623 * Note, in this implementation we support MTD devices with 0x7FFFFFFF 624 * physical eraseblocks maximum. 625 */ 626 627 ubi->peb_size = ubi->mtd->erasesize; 628 ubi->peb_count = mtd_div_by_eb(ubi->mtd->size, ubi->mtd); 629 ubi->flash_size = ubi->mtd->size; 630 631 if (mtd_can_have_bb(ubi->mtd)) { 632 ubi->bad_allowed = 1; 633 ubi->bad_peb_limit = get_bad_peb_limit(ubi, max_beb_per1024); 634 } 635 636 if (ubi->mtd->type == MTD_NORFLASH) 637 ubi->nor_flash = 1; 638 639 ubi->min_io_size = ubi->mtd->writesize; 640 ubi->hdrs_min_io_size = ubi->mtd->writesize >> ubi->mtd->subpage_sft; 641 642 /* 643 * Make sure minimal I/O unit is power of 2. Note, there is no 644 * fundamental reason for this assumption. It is just an optimization 645 * which allows us to avoid costly division operations. 646 */ 647 if (!is_power_of_2(ubi->min_io_size)) { 648 ubi_err(ubi, "min. I/O unit (%d) is not power of 2", 649 ubi->min_io_size); 650 return -EINVAL; 651 } 652 653 ubi_assert(ubi->hdrs_min_io_size > 0); 654 ubi_assert(ubi->hdrs_min_io_size <= ubi->min_io_size); 655 ubi_assert(ubi->min_io_size % ubi->hdrs_min_io_size == 0); 656 657 ubi->max_write_size = ubi->mtd->writebufsize; 658 /* 659 * Maximum write size has to be greater or equivalent to min. I/O 660 * size, and be multiple of min. I/O size. 661 */ 662 if (ubi->max_write_size < ubi->min_io_size || 663 ubi->max_write_size % ubi->min_io_size || 664 !is_power_of_2(ubi->max_write_size)) { 665 ubi_err(ubi, "bad write buffer size %d for %d min. I/O unit", 666 ubi->max_write_size, ubi->min_io_size); 667 return -EINVAL; 668 } 669 670 /* Calculate default aligned sizes of EC and VID headers */ 671 ubi->ec_hdr_alsize = ALIGN(UBI_EC_HDR_SIZE, ubi->hdrs_min_io_size); 672 ubi->vid_hdr_alsize = ALIGN(UBI_VID_HDR_SIZE, ubi->hdrs_min_io_size); 673 674 dbg_gen("min_io_size %d", ubi->min_io_size); 675 dbg_gen("max_write_size %d", ubi->max_write_size); 676 dbg_gen("hdrs_min_io_size %d", ubi->hdrs_min_io_size); 677 dbg_gen("ec_hdr_alsize %d", ubi->ec_hdr_alsize); 678 dbg_gen("vid_hdr_alsize %d", ubi->vid_hdr_alsize); 679 680 if (ubi->vid_hdr_offset == 0) 681 /* Default offset */ 682 ubi->vid_hdr_offset = ubi->vid_hdr_aloffset = 683 ubi->ec_hdr_alsize; 684 else { 685 ubi->vid_hdr_aloffset = ubi->vid_hdr_offset & 686 ~(ubi->hdrs_min_io_size - 1); 687 ubi->vid_hdr_shift = ubi->vid_hdr_offset - 688 ubi->vid_hdr_aloffset; 689 } 690 691 /* 692 * Memory allocation for VID header is ubi->vid_hdr_alsize 693 * which is described in comments in io.c. 694 * Make sure VID header shift + UBI_VID_HDR_SIZE not exceeds 695 * ubi->vid_hdr_alsize, so that all vid header operations 696 * won't access memory out of bounds. 697 */ 698 if ((ubi->vid_hdr_shift + UBI_VID_HDR_SIZE) > ubi->vid_hdr_alsize) { 699 ubi_err(ubi, "Invalid VID header offset %d, VID header shift(%d)" 700 " + VID header size(%zu) > VID header aligned size(%d).", 701 ubi->vid_hdr_offset, ubi->vid_hdr_shift, 702 UBI_VID_HDR_SIZE, ubi->vid_hdr_alsize); 703 return -EINVAL; 704 } 705 706 /* Similar for the data offset */ 707 ubi->leb_start = ubi->vid_hdr_offset + UBI_VID_HDR_SIZE; 708 ubi->leb_start = ALIGN(ubi->leb_start, ubi->min_io_size); 709 710 dbg_gen("vid_hdr_offset %d", ubi->vid_hdr_offset); 711 dbg_gen("vid_hdr_aloffset %d", ubi->vid_hdr_aloffset); 712 dbg_gen("vid_hdr_shift %d", ubi->vid_hdr_shift); 713 dbg_gen("leb_start %d", ubi->leb_start); 714 715 /* The shift must be aligned to 32-bit boundary */ 716 if (ubi->vid_hdr_shift % 4) { 717 ubi_err(ubi, "unaligned VID header shift %d", 718 ubi->vid_hdr_shift); 719 return -EINVAL; 720 } 721 722 /* Check sanity */ 723 if (ubi->vid_hdr_offset < UBI_EC_HDR_SIZE || 724 ubi->leb_start < ubi->vid_hdr_offset + UBI_VID_HDR_SIZE || 725 ubi->leb_start > ubi->peb_size - UBI_VID_HDR_SIZE || 726 ubi->leb_start & (ubi->min_io_size - 1)) { 727 ubi_err(ubi, "bad VID header (%d) or data offsets (%d)", 728 ubi->vid_hdr_offset, ubi->leb_start); 729 return -EINVAL; 730 } 731 732 /* 733 * Set maximum amount of physical erroneous eraseblocks to be 10%. 734 * Erroneous PEB are those which have read errors. 735 */ 736 ubi->max_erroneous = ubi->peb_count / 10; 737 if (ubi->max_erroneous < 16) 738 ubi->max_erroneous = 16; 739 dbg_gen("max_erroneous %d", ubi->max_erroneous); 740 741 /* 742 * It may happen that EC and VID headers are situated in one minimal 743 * I/O unit. In this case we can only accept this UBI image in 744 * read-only mode. 745 */ 746 if (ubi->vid_hdr_offset + UBI_VID_HDR_SIZE <= ubi->hdrs_min_io_size) { 747 ubi_warn(ubi, "EC and VID headers are in the same minimal I/O unit, switch to read-only mode"); 748 ubi->ro_mode = 1; 749 } 750 751 ubi->leb_size = ubi->peb_size - ubi->leb_start; 752 753 if (!(ubi->mtd->flags & MTD_WRITEABLE)) { 754 ubi_msg(ubi, "MTD device %d is write-protected, attach in read-only mode", 755 ubi->mtd->index); 756 ubi->ro_mode = 1; 757 } 758 759 /* 760 * Note, ideally, we have to initialize @ubi->bad_peb_count here. But 761 * unfortunately, MTD does not provide this information. We should loop 762 * over all physical eraseblocks and invoke mtd->block_is_bad() for 763 * each physical eraseblock. So, we leave @ubi->bad_peb_count 764 * uninitialized so far. 765 */ 766 767 return 0; 768 } 769 770 /** 771 * autoresize - re-size the volume which has the "auto-resize" flag set. 772 * @ubi: UBI device description object 773 * @vol_id: ID of the volume to re-size 774 * 775 * This function re-sizes the volume marked by the %UBI_VTBL_AUTORESIZE_FLG in 776 * the volume table to the largest possible size. See comments in ubi-header.h 777 * for more description of the flag. Returns zero in case of success and a 778 * negative error code in case of failure. 779 */ 780 static int autoresize(struct ubi_device *ubi, int vol_id) 781 { 782 struct ubi_volume_desc desc; 783 struct ubi_volume *vol = ubi->volumes[vol_id]; 784 int err, old_reserved_pebs = vol->reserved_pebs; 785 786 if (ubi->ro_mode) { 787 ubi_warn(ubi, "skip auto-resize because of R/O mode"); 788 return 0; 789 } 790 791 /* 792 * Clear the auto-resize flag in the volume in-memory copy of the 793 * volume table, and 'ubi_resize_volume()' will propagate this change 794 * to the flash. 795 */ 796 ubi->vtbl[vol_id].flags &= ~UBI_VTBL_AUTORESIZE_FLG; 797 798 if (ubi->avail_pebs == 0) { 799 struct ubi_vtbl_record vtbl_rec; 800 801 /* 802 * No available PEBs to re-size the volume, clear the flag on 803 * flash and exit. 804 */ 805 vtbl_rec = ubi->vtbl[vol_id]; 806 err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec); 807 if (err) 808 ubi_err(ubi, "cannot clean auto-resize flag for volume %d", 809 vol_id); 810 } else { 811 desc.vol = vol; 812 err = ubi_resize_volume(&desc, 813 old_reserved_pebs + ubi->avail_pebs); 814 if (err) 815 ubi_err(ubi, "cannot auto-resize volume %d", 816 vol_id); 817 } 818 819 if (err) 820 return err; 821 822 ubi_msg(ubi, "volume %d (\"%s\") re-sized from %d to %d LEBs", 823 vol_id, vol->name, old_reserved_pebs, vol->reserved_pebs); 824 return 0; 825 } 826 827 /** 828 * ubi_attach_mtd_dev - attach an MTD device. 829 * @mtd: MTD device description object 830 * @ubi_num: number to assign to the new UBI device 831 * @vid_hdr_offset: VID header offset 832 * @max_beb_per1024: maximum expected number of bad PEB per 1024 PEBs 833 * @disable_fm: whether disable fastmap 834 * @need_resv_pool: whether reserve pebs to fill fm_pool 835 * 836 * This function attaches MTD device @mtd_dev to UBI and assign @ubi_num number 837 * to the newly created UBI device, unless @ubi_num is %UBI_DEV_NUM_AUTO, in 838 * which case this function finds a vacant device number and assigns it 839 * automatically. Returns the new UBI device number in case of success and a 840 * negative error code in case of failure. 841 * 842 * If @disable_fm is true, ubi doesn't create new fastmap even the module param 843 * 'fm_autoconvert' is set, and existed old fastmap will be destroyed after 844 * doing full scanning. 845 * 846 * Note, the invocations of this function has to be serialized by the 847 * @ubi_devices_mutex. 848 */ 849 int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num, 850 int vid_hdr_offset, int max_beb_per1024, bool disable_fm, 851 bool need_resv_pool) 852 { 853 struct ubi_device *ubi; 854 int i, err; 855 856 if (max_beb_per1024 < 0 || max_beb_per1024 > MAX_MTD_UBI_BEB_LIMIT) 857 return -EINVAL; 858 859 if (!max_beb_per1024) 860 max_beb_per1024 = CONFIG_MTD_UBI_BEB_LIMIT; 861 862 /* 863 * Check if we already have the same MTD device attached. 864 * 865 * Note, this function assumes that UBI devices creations and deletions 866 * are serialized, so it does not take the &ubi_devices_lock. 867 */ 868 for (i = 0; i < UBI_MAX_DEVICES; i++) { 869 ubi = ubi_devices[i]; 870 if (ubi && mtd->index == ubi->mtd->index) { 871 pr_err("ubi: mtd%d is already attached to ubi%d\n", 872 mtd->index, i); 873 return -EEXIST; 874 } 875 } 876 877 /* 878 * Make sure this MTD device is not emulated on top of an UBI volume 879 * already. Well, generally this recursion works fine, but there are 880 * different problems like the UBI module takes a reference to itself 881 * by attaching (and thus, opening) the emulated MTD device. This 882 * results in inability to unload the module. And in general it makes 883 * no sense to attach emulated MTD devices, so we prohibit this. 884 */ 885 if (mtd->type == MTD_UBIVOLUME) { 886 pr_err("ubi: refuse attaching mtd%d - it is already emulated on top of UBI\n", 887 mtd->index); 888 return -EINVAL; 889 } 890 891 /* 892 * Both UBI and UBIFS have been designed for SLC NAND and NOR flashes. 893 * MLC NAND is different and needs special care, otherwise UBI or UBIFS 894 * will die soon and you will lose all your data. 895 * Relax this rule if the partition we're attaching to operates in SLC 896 * mode. 897 */ 898 if (mtd->type == MTD_MLCNANDFLASH && 899 !(mtd->flags & MTD_SLC_ON_MLC_EMULATION)) { 900 pr_err("ubi: refuse attaching mtd%d - MLC NAND is not supported\n", 901 mtd->index); 902 return -EINVAL; 903 } 904 905 /* UBI cannot work on flashes with zero erasesize. */ 906 if (!mtd->erasesize) { 907 pr_err("ubi: refuse attaching mtd%d - zero erasesize flash is not supported\n", 908 mtd->index); 909 return -EINVAL; 910 } 911 912 if (ubi_num == UBI_DEV_NUM_AUTO) { 913 /* Search for an empty slot in the @ubi_devices array */ 914 for (ubi_num = 0; ubi_num < UBI_MAX_DEVICES; ubi_num++) 915 if (!ubi_devices[ubi_num]) 916 break; 917 if (ubi_num == UBI_MAX_DEVICES) { 918 pr_err("ubi: only %d UBI devices may be created\n", 919 UBI_MAX_DEVICES); 920 return -ENFILE; 921 } 922 } else { 923 if (ubi_num >= UBI_MAX_DEVICES) 924 return -EINVAL; 925 926 /* Make sure ubi_num is not busy */ 927 if (ubi_devices[ubi_num]) { 928 pr_err("ubi: ubi%i already exists\n", ubi_num); 929 return -EEXIST; 930 } 931 } 932 933 ubi = kzalloc(sizeof(struct ubi_device), GFP_KERNEL); 934 if (!ubi) 935 return -ENOMEM; 936 937 device_initialize(&ubi->dev); 938 ubi->dev.release = dev_release; 939 ubi->dev.class = &ubi_class; 940 ubi->dev.groups = ubi_dev_groups; 941 ubi->dev.parent = &mtd->dev; 942 943 ubi->mtd = mtd; 944 ubi->ubi_num = ubi_num; 945 ubi->vid_hdr_offset = vid_hdr_offset; 946 ubi->autoresize_vol_id = -1; 947 948 #ifdef CONFIG_MTD_UBI_FASTMAP 949 ubi->fm_pool.used = ubi->fm_pool.size = 0; 950 ubi->fm_wl_pool.used = ubi->fm_wl_pool.size = 0; 951 952 /* 953 * fm_pool.max_size is 5% of the total number of PEBs but it's also 954 * between UBI_FM_MAX_POOL_SIZE and UBI_FM_MIN_POOL_SIZE. 955 */ 956 ubi->fm_pool.max_size = min(((int)mtd_div_by_eb(ubi->mtd->size, 957 ubi->mtd) / 100) * 5, UBI_FM_MAX_POOL_SIZE); 958 ubi->fm_pool.max_size = max(ubi->fm_pool.max_size, 959 UBI_FM_MIN_POOL_SIZE); 960 961 ubi->fm_wl_pool.max_size = ubi->fm_pool.max_size / 2; 962 ubi->fm_pool_rsv_cnt = need_resv_pool ? ubi->fm_pool.max_size : 0; 963 ubi->fm_disabled = (!fm_autoconvert || disable_fm) ? 1 : 0; 964 if (fm_debug) 965 ubi_enable_dbg_chk_fastmap(ubi); 966 967 if (!ubi->fm_disabled && (int)mtd_div_by_eb(ubi->mtd->size, ubi->mtd) 968 <= UBI_FM_MAX_START) { 969 ubi_err(ubi, "More than %i PEBs are needed for fastmap, sorry.", 970 UBI_FM_MAX_START); 971 ubi->fm_disabled = 1; 972 } 973 974 ubi_msg(ubi, "default fastmap pool size: %d", ubi->fm_pool.max_size); 975 ubi_msg(ubi, "default fastmap WL pool size: %d", 976 ubi->fm_wl_pool.max_size); 977 #else 978 ubi->fm_disabled = 1; 979 #endif 980 mutex_init(&ubi->buf_mutex); 981 mutex_init(&ubi->ckvol_mutex); 982 mutex_init(&ubi->device_mutex); 983 spin_lock_init(&ubi->volumes_lock); 984 init_rwsem(&ubi->fm_protect); 985 init_rwsem(&ubi->fm_eba_sem); 986 987 ubi_msg(ubi, "attaching mtd%d", mtd->index); 988 989 err = io_init(ubi, max_beb_per1024); 990 if (err) 991 goto out_free; 992 993 err = -ENOMEM; 994 ubi->peb_buf = vmalloc(ubi->peb_size); 995 if (!ubi->peb_buf) 996 goto out_free; 997 998 #ifdef CONFIG_MTD_UBI_FASTMAP 999 ubi->fm_size = ubi_calc_fm_size(ubi); 1000 ubi->fm_buf = vzalloc(ubi->fm_size); 1001 if (!ubi->fm_buf) 1002 goto out_free; 1003 #endif 1004 err = ubi_attach(ubi, disable_fm ? 1 : 0); 1005 if (err) { 1006 ubi_err(ubi, "failed to attach mtd%d, error %d", 1007 mtd->index, err); 1008 goto out_free; 1009 } 1010 1011 if (ubi->autoresize_vol_id != -1) { 1012 err = autoresize(ubi, ubi->autoresize_vol_id); 1013 if (err) 1014 goto out_detach; 1015 } 1016 1017 err = uif_init(ubi); 1018 if (err) 1019 goto out_detach; 1020 1021 err = ubi_debugfs_init_dev(ubi); 1022 if (err) 1023 goto out_uif; 1024 1025 ubi->bgt_thread = kthread_create(ubi_thread, ubi, "%s", ubi->bgt_name); 1026 if (IS_ERR(ubi->bgt_thread)) { 1027 err = PTR_ERR(ubi->bgt_thread); 1028 ubi_err(ubi, "cannot spawn \"%s\", error %d", 1029 ubi->bgt_name, err); 1030 goto out_debugfs; 1031 } 1032 1033 ubi_msg(ubi, "attached mtd%d (name \"%s\", size %llu MiB)", 1034 mtd->index, mtd->name, ubi->flash_size >> 20); 1035 ubi_msg(ubi, "PEB size: %d bytes (%d KiB), LEB size: %d bytes", 1036 ubi->peb_size, ubi->peb_size >> 10, ubi->leb_size); 1037 ubi_msg(ubi, "min./max. I/O unit sizes: %d/%d, sub-page size %d", 1038 ubi->min_io_size, ubi->max_write_size, ubi->hdrs_min_io_size); 1039 ubi_msg(ubi, "VID header offset: %d (aligned %d), data offset: %d", 1040 ubi->vid_hdr_offset, ubi->vid_hdr_aloffset, ubi->leb_start); 1041 ubi_msg(ubi, "good PEBs: %d, bad PEBs: %d, corrupted PEBs: %d", 1042 ubi->good_peb_count, ubi->bad_peb_count, ubi->corr_peb_count); 1043 ubi_msg(ubi, "user volume: %d, internal volumes: %d, max. volumes count: %d", 1044 ubi->vol_count - UBI_INT_VOL_COUNT, UBI_INT_VOL_COUNT, 1045 ubi->vtbl_slots); 1046 ubi_msg(ubi, "max/mean erase counter: %d/%d, WL threshold: %d, image sequence number: %u", 1047 ubi->max_ec, ubi->mean_ec, CONFIG_MTD_UBI_WL_THRESHOLD, 1048 ubi->image_seq); 1049 ubi_msg(ubi, "available PEBs: %d, total reserved PEBs: %d, PEBs reserved for bad PEB handling: %d", 1050 ubi->avail_pebs, ubi->rsvd_pebs, ubi->beb_rsvd_pebs); 1051 1052 /* 1053 * The below lock makes sure we do not race with 'ubi_thread()' which 1054 * checks @ubi->thread_enabled. Otherwise we may fail to wake it up. 1055 */ 1056 spin_lock(&ubi->wl_lock); 1057 ubi->thread_enabled = 1; 1058 wake_up_process(ubi->bgt_thread); 1059 spin_unlock(&ubi->wl_lock); 1060 1061 ubi_devices[ubi_num] = ubi; 1062 ubi_notify_all(ubi, UBI_VOLUME_ADDED, NULL); 1063 return ubi_num; 1064 1065 out_debugfs: 1066 ubi_debugfs_exit_dev(ubi); 1067 out_uif: 1068 uif_close(ubi); 1069 out_detach: 1070 ubi_wl_close(ubi); 1071 ubi_free_all_volumes(ubi); 1072 vfree(ubi->vtbl); 1073 out_free: 1074 vfree(ubi->peb_buf); 1075 vfree(ubi->fm_buf); 1076 put_device(&ubi->dev); 1077 return err; 1078 } 1079 1080 /** 1081 * ubi_detach_mtd_dev - detach an MTD device. 1082 * @ubi_num: UBI device number to detach from 1083 * @anyway: detach MTD even if device reference count is not zero 1084 * 1085 * This function destroys an UBI device number @ubi_num and detaches the 1086 * underlying MTD device. Returns zero in case of success and %-EBUSY if the 1087 * UBI device is busy and cannot be destroyed, and %-EINVAL if it does not 1088 * exist. 1089 * 1090 * Note, the invocations of this function has to be serialized by the 1091 * @ubi_devices_mutex. 1092 */ 1093 int ubi_detach_mtd_dev(int ubi_num, int anyway) 1094 { 1095 struct ubi_device *ubi; 1096 1097 if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES) 1098 return -EINVAL; 1099 1100 ubi = ubi_get_device(ubi_num); 1101 if (!ubi) 1102 return -EINVAL; 1103 1104 spin_lock(&ubi_devices_lock); 1105 ubi->ref_count -= 1; 1106 if (ubi->ref_count) { 1107 if (!anyway) { 1108 spin_unlock(&ubi_devices_lock); 1109 return -EBUSY; 1110 } 1111 /* This may only happen if there is a bug */ 1112 ubi_err(ubi, "%s reference count %d, destroy anyway", 1113 ubi->ubi_name, ubi->ref_count); 1114 } 1115 ubi->is_dead = true; 1116 spin_unlock(&ubi_devices_lock); 1117 1118 ubi_notify_all(ubi, UBI_VOLUME_SHUTDOWN, NULL); 1119 1120 spin_lock(&ubi_devices_lock); 1121 put_device(&ubi->dev); 1122 ubi_devices[ubi_num] = NULL; 1123 spin_unlock(&ubi_devices_lock); 1124 1125 ubi_assert(ubi_num == ubi->ubi_num); 1126 ubi_notify_all(ubi, UBI_VOLUME_REMOVED, NULL); 1127 ubi_msg(ubi, "detaching mtd%d", ubi->mtd->index); 1128 #ifdef CONFIG_MTD_UBI_FASTMAP 1129 /* If we don't write a new fastmap at detach time we lose all 1130 * EC updates that have been made since the last written fastmap. 1131 * In case of fastmap debugging we omit the update to simulate an 1132 * unclean shutdown. */ 1133 if (!ubi_dbg_chk_fastmap(ubi)) 1134 ubi_update_fastmap(ubi); 1135 #endif 1136 /* 1137 * Before freeing anything, we have to stop the background thread to 1138 * prevent it from doing anything on this device while we are freeing. 1139 */ 1140 if (ubi->bgt_thread) 1141 kthread_stop(ubi->bgt_thread); 1142 1143 #ifdef CONFIG_MTD_UBI_FASTMAP 1144 cancel_work_sync(&ubi->fm_work); 1145 #endif 1146 ubi_debugfs_exit_dev(ubi); 1147 uif_close(ubi); 1148 1149 ubi_wl_close(ubi); 1150 ubi_free_internal_volumes(ubi); 1151 vfree(ubi->vtbl); 1152 vfree(ubi->peb_buf); 1153 vfree(ubi->fm_buf); 1154 ubi_msg(ubi, "mtd%d is detached", ubi->mtd->index); 1155 put_mtd_device(ubi->mtd); 1156 put_device(&ubi->dev); 1157 return 0; 1158 } 1159 1160 /** 1161 * open_mtd_by_chdev - open an MTD device by its character device node path. 1162 * @mtd_dev: MTD character device node path 1163 * 1164 * This helper function opens an MTD device by its character node device path. 1165 * Returns MTD device description object in case of success and a negative 1166 * error code in case of failure. 1167 */ 1168 static struct mtd_info * __init open_mtd_by_chdev(const char *mtd_dev) 1169 { 1170 int err, minor; 1171 struct path path; 1172 struct kstat stat; 1173 1174 /* Probably this is an MTD character device node path */ 1175 err = kern_path(mtd_dev, LOOKUP_FOLLOW, &path); 1176 if (err) 1177 return ERR_PTR(err); 1178 1179 err = vfs_getattr(&path, &stat, STATX_TYPE, AT_STATX_SYNC_AS_STAT); 1180 path_put(&path); 1181 if (err) 1182 return ERR_PTR(err); 1183 1184 /* MTD device number is defined by the major / minor numbers */ 1185 if (MAJOR(stat.rdev) != MTD_CHAR_MAJOR || !S_ISCHR(stat.mode)) 1186 return ERR_PTR(-EINVAL); 1187 1188 minor = MINOR(stat.rdev); 1189 1190 if (minor & 1) 1191 /* 1192 * Just do not think the "/dev/mtdrX" devices support is need, 1193 * so do not support them to avoid doing extra work. 1194 */ 1195 return ERR_PTR(-EINVAL); 1196 1197 return get_mtd_device(NULL, minor / 2); 1198 } 1199 1200 /** 1201 * open_mtd_device - open MTD device by name, character device path, or number. 1202 * @mtd_dev: name, character device node path, or MTD device device number 1203 * 1204 * This function tries to open and MTD device described by @mtd_dev string, 1205 * which is first treated as ASCII MTD device number, and if it is not true, it 1206 * is treated as MTD device name, and if that is also not true, it is treated 1207 * as MTD character device node path. Returns MTD device description object in 1208 * case of success and a negative error code in case of failure. 1209 */ 1210 static struct mtd_info * __init open_mtd_device(const char *mtd_dev) 1211 { 1212 struct mtd_info *mtd; 1213 int mtd_num; 1214 char *endp; 1215 1216 mtd_num = simple_strtoul(mtd_dev, &endp, 0); 1217 if (*endp != '\0' || mtd_dev == endp) { 1218 /* 1219 * This does not look like an ASCII integer, probably this is 1220 * MTD device name. 1221 */ 1222 mtd = get_mtd_device_nm(mtd_dev); 1223 if (PTR_ERR(mtd) == -ENODEV) 1224 /* Probably this is an MTD character device node path */ 1225 mtd = open_mtd_by_chdev(mtd_dev); 1226 } else 1227 mtd = get_mtd_device(NULL, mtd_num); 1228 1229 return mtd; 1230 } 1231 1232 static void ubi_notify_add(struct mtd_info *mtd) 1233 { 1234 struct device_node *np = mtd_get_of_node(mtd); 1235 int err; 1236 1237 if (!of_device_is_compatible(np, "linux,ubi")) 1238 return; 1239 1240 /* 1241 * we are already holding &mtd_table_mutex, but still need 1242 * to bump refcount 1243 */ 1244 err = __get_mtd_device(mtd); 1245 if (err) 1246 return; 1247 1248 /* called while holding mtd_table_mutex */ 1249 mutex_lock_nested(&ubi_devices_mutex, SINGLE_DEPTH_NESTING); 1250 err = ubi_attach_mtd_dev(mtd, UBI_DEV_NUM_AUTO, 0, 0, false, false); 1251 mutex_unlock(&ubi_devices_mutex); 1252 if (err < 0) 1253 __put_mtd_device(mtd); 1254 } 1255 1256 static void ubi_notify_remove(struct mtd_info *mtd) 1257 { 1258 /* do nothing for now */ 1259 } 1260 1261 static struct mtd_notifier ubi_mtd_notifier = { 1262 .add = ubi_notify_add, 1263 .remove = ubi_notify_remove, 1264 }; 1265 1266 static int __init ubi_init_attach(void) 1267 { 1268 int err, i, k; 1269 1270 /* Attach MTD devices */ 1271 for (i = 0; i < mtd_devs; i++) { 1272 struct mtd_dev_param *p = &mtd_dev_param[i]; 1273 struct mtd_info *mtd; 1274 1275 cond_resched(); 1276 1277 mtd = open_mtd_device(p->name); 1278 if (IS_ERR(mtd)) { 1279 err = PTR_ERR(mtd); 1280 pr_err("UBI error: cannot open mtd %s, error %d\n", 1281 p->name, err); 1282 /* See comment below re-ubi_is_module(). */ 1283 if (ubi_is_module()) 1284 goto out_detach; 1285 continue; 1286 } 1287 1288 mutex_lock(&ubi_devices_mutex); 1289 err = ubi_attach_mtd_dev(mtd, p->ubi_num, 1290 p->vid_hdr_offs, p->max_beb_per1024, 1291 p->enable_fm == 0, 1292 p->need_resv_pool != 0); 1293 mutex_unlock(&ubi_devices_mutex); 1294 if (err < 0) { 1295 pr_err("UBI error: cannot attach mtd%d\n", 1296 mtd->index); 1297 put_mtd_device(mtd); 1298 1299 /* 1300 * Originally UBI stopped initializing on any error. 1301 * However, later on it was found out that this 1302 * behavior is not very good when UBI is compiled into 1303 * the kernel and the MTD devices to attach are passed 1304 * through the command line. Indeed, UBI failure 1305 * stopped whole boot sequence. 1306 * 1307 * To fix this, we changed the behavior for the 1308 * non-module case, but preserved the old behavior for 1309 * the module case, just for compatibility. This is a 1310 * little inconsistent, though. 1311 */ 1312 if (ubi_is_module()) 1313 goto out_detach; 1314 } 1315 } 1316 1317 return 0; 1318 1319 out_detach: 1320 for (k = 0; k < i; k++) 1321 if (ubi_devices[k]) { 1322 mutex_lock(&ubi_devices_mutex); 1323 ubi_detach_mtd_dev(ubi_devices[k]->ubi_num, 1); 1324 mutex_unlock(&ubi_devices_mutex); 1325 } 1326 return err; 1327 } 1328 #ifndef CONFIG_MTD_UBI_MODULE 1329 late_initcall(ubi_init_attach); 1330 #endif 1331 1332 static int __init ubi_init(void) 1333 { 1334 int err; 1335 1336 /* Ensure that EC and VID headers have correct size */ 1337 BUILD_BUG_ON(sizeof(struct ubi_ec_hdr) != 64); 1338 BUILD_BUG_ON(sizeof(struct ubi_vid_hdr) != 64); 1339 1340 if (mtd_devs > UBI_MAX_DEVICES) { 1341 pr_err("UBI error: too many MTD devices, maximum is %d\n", 1342 UBI_MAX_DEVICES); 1343 return -EINVAL; 1344 } 1345 1346 /* Create base sysfs directory and sysfs files */ 1347 err = class_register(&ubi_class); 1348 if (err < 0) 1349 return err; 1350 1351 err = misc_register(&ubi_ctrl_cdev); 1352 if (err) { 1353 pr_err("UBI error: cannot register device\n"); 1354 goto out; 1355 } 1356 1357 ubi_wl_entry_slab = kmem_cache_create("ubi_wl_entry_slab", 1358 sizeof(struct ubi_wl_entry), 1359 0, 0, NULL); 1360 if (!ubi_wl_entry_slab) { 1361 err = -ENOMEM; 1362 goto out_dev_unreg; 1363 } 1364 1365 err = ubi_debugfs_init(); 1366 if (err) 1367 goto out_slab; 1368 1369 err = ubiblock_init(); 1370 if (err) { 1371 pr_err("UBI error: block: cannot initialize, error %d\n", err); 1372 1373 /* See comment above re-ubi_is_module(). */ 1374 if (ubi_is_module()) 1375 goto out_slab; 1376 } 1377 1378 register_mtd_user(&ubi_mtd_notifier); 1379 1380 if (ubi_is_module()) { 1381 err = ubi_init_attach(); 1382 if (err) 1383 goto out_mtd_notifier; 1384 } 1385 1386 return 0; 1387 1388 out_mtd_notifier: 1389 unregister_mtd_user(&ubi_mtd_notifier); 1390 out_slab: 1391 kmem_cache_destroy(ubi_wl_entry_slab); 1392 out_dev_unreg: 1393 misc_deregister(&ubi_ctrl_cdev); 1394 out: 1395 class_unregister(&ubi_class); 1396 pr_err("UBI error: cannot initialize UBI, error %d\n", err); 1397 return err; 1398 } 1399 device_initcall(ubi_init); 1400 1401 1402 static void __exit ubi_exit(void) 1403 { 1404 int i; 1405 1406 ubiblock_exit(); 1407 unregister_mtd_user(&ubi_mtd_notifier); 1408 1409 for (i = 0; i < UBI_MAX_DEVICES; i++) 1410 if (ubi_devices[i]) { 1411 mutex_lock(&ubi_devices_mutex); 1412 ubi_detach_mtd_dev(ubi_devices[i]->ubi_num, 1); 1413 mutex_unlock(&ubi_devices_mutex); 1414 } 1415 ubi_debugfs_exit(); 1416 kmem_cache_destroy(ubi_wl_entry_slab); 1417 misc_deregister(&ubi_ctrl_cdev); 1418 class_unregister(&ubi_class); 1419 } 1420 module_exit(ubi_exit); 1421 1422 /** 1423 * bytes_str_to_int - convert a number of bytes string into an integer. 1424 * @str: the string to convert 1425 * 1426 * This function returns positive resulting integer in case of success and a 1427 * negative error code in case of failure. 1428 */ 1429 static int bytes_str_to_int(const char *str) 1430 { 1431 char *endp; 1432 unsigned long result; 1433 1434 result = simple_strtoul(str, &endp, 0); 1435 if (str == endp || result >= INT_MAX) { 1436 pr_err("UBI error: incorrect bytes count: \"%s\"\n", str); 1437 return -EINVAL; 1438 } 1439 1440 switch (*endp) { 1441 case 'G': 1442 result *= 1024; 1443 fallthrough; 1444 case 'M': 1445 result *= 1024; 1446 fallthrough; 1447 case 'K': 1448 result *= 1024; 1449 break; 1450 case '\0': 1451 break; 1452 default: 1453 pr_err("UBI error: incorrect bytes count: \"%s\"\n", str); 1454 return -EINVAL; 1455 } 1456 1457 return result; 1458 } 1459 1460 /** 1461 * ubi_mtd_param_parse - parse the 'mtd=' UBI parameter. 1462 * @val: the parameter value to parse 1463 * @kp: not used 1464 * 1465 * This function returns zero in case of success and a negative error code in 1466 * case of error. 1467 */ 1468 static int ubi_mtd_param_parse(const char *val, const struct kernel_param *kp) 1469 { 1470 int i, len; 1471 struct mtd_dev_param *p; 1472 char buf[MTD_PARAM_LEN_MAX]; 1473 char *pbuf = &buf[0]; 1474 char *tokens[MTD_PARAM_MAX_COUNT], *token; 1475 1476 if (!val) 1477 return -EINVAL; 1478 1479 if (mtd_devs == UBI_MAX_DEVICES) { 1480 pr_err("UBI error: too many parameters, max. is %d\n", 1481 UBI_MAX_DEVICES); 1482 return -EINVAL; 1483 } 1484 1485 len = strnlen(val, MTD_PARAM_LEN_MAX); 1486 if (len == MTD_PARAM_LEN_MAX) { 1487 pr_err("UBI error: parameter \"%s\" is too long, max. is %d\n", 1488 val, MTD_PARAM_LEN_MAX); 1489 return -EINVAL; 1490 } 1491 1492 if (len == 0) { 1493 pr_warn("UBI warning: empty 'mtd=' parameter - ignored\n"); 1494 return 0; 1495 } 1496 1497 strcpy(buf, val); 1498 1499 /* Get rid of the final newline */ 1500 if (buf[len - 1] == '\n') 1501 buf[len - 1] = '\0'; 1502 1503 for (i = 0; i < MTD_PARAM_MAX_COUNT; i++) 1504 tokens[i] = strsep(&pbuf, ","); 1505 1506 if (pbuf) { 1507 pr_err("UBI error: too many arguments at \"%s\"\n", val); 1508 return -EINVAL; 1509 } 1510 1511 p = &mtd_dev_param[mtd_devs]; 1512 strcpy(&p->name[0], tokens[0]); 1513 1514 token = tokens[1]; 1515 if (token) { 1516 p->vid_hdr_offs = bytes_str_to_int(token); 1517 1518 if (p->vid_hdr_offs < 0) 1519 return p->vid_hdr_offs; 1520 } 1521 1522 token = tokens[2]; 1523 if (token) { 1524 int err = kstrtoint(token, 10, &p->max_beb_per1024); 1525 1526 if (err) { 1527 pr_err("UBI error: bad value for max_beb_per1024 parameter: %s\n", 1528 token); 1529 return -EINVAL; 1530 } 1531 } 1532 1533 token = tokens[3]; 1534 if (token) { 1535 int err = kstrtoint(token, 10, &p->ubi_num); 1536 1537 if (err) { 1538 pr_err("UBI error: bad value for ubi_num parameter: %s\n", 1539 token); 1540 return -EINVAL; 1541 } 1542 } else 1543 p->ubi_num = UBI_DEV_NUM_AUTO; 1544 1545 token = tokens[4]; 1546 if (token) { 1547 int err = kstrtoint(token, 10, &p->enable_fm); 1548 1549 if (err) { 1550 pr_err("UBI error: bad value for enable_fm parameter: %s\n", 1551 token); 1552 return -EINVAL; 1553 } 1554 } else 1555 p->enable_fm = 0; 1556 1557 token = tokens[5]; 1558 if (token) { 1559 int err = kstrtoint(token, 10, &p->need_resv_pool); 1560 1561 if (err) { 1562 pr_err("UBI error: bad value for need_resv_pool parameter: %s\n", 1563 token); 1564 return -EINVAL; 1565 } 1566 } else 1567 p->need_resv_pool = 0; 1568 1569 mtd_devs += 1; 1570 return 0; 1571 } 1572 1573 module_param_call(mtd, ubi_mtd_param_parse, NULL, NULL, 0400); 1574 MODULE_PARM_DESC(mtd, "MTD devices to attach. Parameter format: mtd=<name|num|path>[,<vid_hdr_offs>[,max_beb_per1024[,ubi_num]]].\n" 1575 "Multiple \"mtd\" parameters may be specified.\n" 1576 "MTD devices may be specified by their number, name, or path to the MTD character device node.\n" 1577 "Optional \"vid_hdr_offs\" parameter specifies UBI VID header position to be used by UBI. (default value if 0)\n" 1578 "Optional \"max_beb_per1024\" parameter specifies the maximum expected bad eraseblock per 1024 eraseblocks. (default value (" 1579 __stringify(CONFIG_MTD_UBI_BEB_LIMIT) ") if 0)\n" 1580 "Optional \"ubi_num\" parameter specifies UBI device number which have to be assigned to the newly created UBI device (assigned automatically by default)\n" 1581 "Optional \"enable_fm\" parameter determines whether to enable fastmap during attach. If the value is non-zero, fastmap is enabled. Default value is 0.\n" 1582 "Optional \"need_resv_pool\" parameter determines whether to reserve pool->max_size pebs during attach. If the value is non-zero, peb reservation is enabled. Default value is 0.\n" 1583 "\n" 1584 "Example 1: mtd=/dev/mtd0 - attach MTD device /dev/mtd0.\n" 1585 "Example 2: mtd=content,1984 mtd=4 - attach MTD device with name \"content\" using VID header offset 1984, and MTD device number 4 with default VID header offset.\n" 1586 "Example 3: mtd=/dev/mtd1,0,25 - attach MTD device /dev/mtd1 using default VID header offset and reserve 25*nand_size_in_blocks/1024 erase blocks for bad block handling.\n" 1587 "Example 4: mtd=/dev/mtd1,0,0,5 - attach MTD device /dev/mtd1 to UBI 5 and using default values for the other fields.\n" 1588 "example 5: mtd=1,0,0,5 mtd=2,0,0,6,1 - attach MTD device /dev/mtd1 to UBI 5 and disable fastmap; attach MTD device /dev/mtd2 to UBI 6 and enable fastmap.(only works when fastmap is enabled and fm_autoconvert=Y).\n" 1589 "\t(e.g. if the NAND *chipset* has 4096 PEB, 100 will be reserved for this UBI device)."); 1590 #ifdef CONFIG_MTD_UBI_FASTMAP 1591 module_param(fm_autoconvert, bool, 0644); 1592 MODULE_PARM_DESC(fm_autoconvert, "Set this parameter to enable fastmap automatically on images without a fastmap."); 1593 module_param(fm_debug, bool, 0); 1594 MODULE_PARM_DESC(fm_debug, "Set this parameter to enable fastmap debugging by default. Warning, this will make fastmap slow!"); 1595 #endif 1596 MODULE_VERSION(__stringify(UBI_VERSION)); 1597 MODULE_DESCRIPTION("UBI - Unsorted Block Images"); 1598 MODULE_AUTHOR("Artem Bityutskiy"); 1599 MODULE_LICENSE("GPL"); 1600